Major architectural mistakes

Putting your employee punch-clock on the InternetSo everyone's wages depend on clocking-in, but ADP decides to make its "ezLaborManager" a web site on the public internet. Now people don't get paid for the time when the web site or Internet connection is down

Stealing focusA design mistake seen in Windows, so that if you're typing an email and a "Delete your entire database?" message pops up from a background task, you better hope you weren't writing a sentence with a 'Y' in it at the time